Series I pickup levels with a DS-5

[backdoor_hippie]

I just got my Alembic Series I a little over a week ago, and the DS-5 and cable to go with it came last night. I finally had a chance to test it out today and noticed that there are variations in the pickup volume depending on how I have the DS-5 and pickup selector set.  With the DS-5 set to Mono I get a distinct volume drop when I change the pickup selector from both pickups to either just the neck or just the bridge.  But if I keep the selector in the center position and just turn one pickup down I don't get that drop.  At the same time, if I have the pickup selector to neck only I will get a volume boost when I change the DS-5 from Mono to Stereo and use just the bass output.  
 
In other words, DS-5 set to Mono, it's louder in the center pickup selector switch position than it is in either of the individual pickup selector positions, but with it set to Stereo there is no volume drop.
 
Is this normal?  I can't imagine that it is.  Any advice or threads to check?  I did a search and found pickup balance questions, but nothing like this.  Balance between the pickups is fine, it's just a drop when using one pickup at a time blended by the DS-5.
 
Help!

[keith_h]

Yes it's normal. In mono mode the pickups are additive so it will be louder when on the center position.  
 
Keith

[edwin]

I have noted this as well. However, I have to say that my current Series I, which has a blend control instead of individual volumes and a selector switch, has a very consistent volume from pickup to pickup regardless of settings.